/Engine/Source/Runtime/Landscape/Classes/LandscapeInfo.h
Updates the spline registrations (with ALL landscape infos) when a spline has changed the landscape it is targeting
static void UpdateRegistrationForSplineActor ( [UWorld](API\Runtime\Engine\Engine\UWorld) * InWorld, [TScriptInterface](API\Runtime\CoreUObject\UObject\TScriptInterface)< [ILandscapeSplineInterface](API\Runtime\Landscape\ILandscapeSplineInterface) > InSplineActor )